Heat-sealing apparatus



Oct. 19, 1948. GARDNER r 2,451,728

HEAT-SEALING APPARATUS Filed A ril 17, 1945 2 Sheets-Sheet i An mun A- Ganousn I IMO I for! G. M4: (olnncg I By P ATTORNEY.

- 1948- A. A. GARD NER Er'AL 2,451,728

HEAT-SEALING APPARATUS Filed April 17, 1945 2 Sheets-Sheet 2 BY FM 40.41%

ATTORNEY.

UNITED s'rA'r Patented a. 19.1948

= r Hen-8m Arraauus Arthnr a. earns, f New York, N. 1.,

John G. Maccormack, rs to Brellee Mfg. Con

Pony, New York, a copartnership Application Aprll l'lglflfi, Serial No. 588,826

' g 1 jwi. 154-42) ratus.

the latter isconveyed by said bands Another object of the'invention is to provide a heat-sealing apparatus of the endless band type with means for preheating the heat scalable material without the application of pressure thereto.

A yet further object orally to improve the construction and operation of heat-sealing apparatus of the endless band type.- I

The above and other objects, features and advantages of the invention will be fully under-'- stood irom the following description, considered in connection with the accompanying illustrative drawings. g

In thedrawings: I

Fig. 1 is a plan view of a heat-sealing apparatus embodying the present invention, 'a portion of one of the endless bands being cut away for the purpose of illustration;

Fig. 2 is a view on the line 2-2 of Fig. 1;

Fig. 3 is a view on the line 3-3 of Fig. 2;

Fig. 4 is a 'view, on a larger scale, partly in elevation and partly in section, on the line 4-4 of Fig. 1;

Fig. 5 is a sectional view, on the line 5-5 of Fi 1;

Fig. 6 is a fragmentary perspective'view of tubular material having overlapping marginal edge portions heat sealed to each other.

Referring now to the drawings in detail, the heat-sealingv apparatus of the present invention comprises upper and lower endless bands Ill and I2, respectively, formed of steel or other suitable a larger scale, on

' metal or heat conducting material. Band ill passes over metal drums I 4 and I 8 carried and rotated by shafts l8 and 20, respectively. Drum N is'driven by a sprocket wheel 22 or by any other suitable mechnism connected for power operation. The lower endless band l2 passes over rotary drums 24 and 28, drum 24 being preferably driven for moving band I2 atthe some linear speed as band ill. The lower run This invention relates to heat-sealing appa 7 i lowerl l'l dlnal run of band it against the The primary object'of thepresent invention is to provide a heat-sealing apparatus constructed .and arranged to applyv heat and pressurevby means of a pair of movable'endless bands to overlapping portions of heat scalable material while I 7 .(Figs. 4 and 5). Housing 30 is carried by a Provision is made for resiliently pressing the adjacent upper or confronting longitudinal run of band 12. For this purpose and also for applying heat to band Ill, a plurality of rollers 28 carried by a housing 30 are arranged to engage the upper surface'of the lower run of band l0 ,bracket 22 pivotally mounted at one end thereof arms .38 which are pivotally connected to the top.

of the invention'is gen-' g the lower arm ofupper band It by gravity and of housing ill by means of pins 38 carried by lugs 40 fixed to the top of said housing. The rollers 2' which are carried by housing 30 press against are also urged against said run of the-band by spring means, here shown as a compression spring 42 which, as clearly illustrated in Fig. -5, bears at one end thereof against a part 44 fixed tohousing 20, the opposite. end of said spring bearing against a washer 48 held adiustably by a nut 48 on a post 50 carried, by'a partof the stationary frame F. The pivotal connection of the housing It to bracket}: provides for maintaining the band-engaging surfaces of rollers 28 in a horizontal plane.

An electric heater 52 of any suitable type is mounted within housing 30 for heating rollers 28 carried by said housing whereby to apply heat through said rollers to band Ill. The heat seal,- able material, which for example, may be in the form of a tube T (Fig. 6), provided with overlapped marginal edge portions Tiand T2 which are to be heat sealed to each other is carried by and between bands Ill and 12 through the pressure and heat applying zone which extends longi tudinally of housing 3'0 and for a substantial length of the confronting or companion runs or portions of bands in and i2.

' We prefer to provide meas in addition to the heated rollers 28 for heating band l0. Thus as shown, an electric heater 54 is positioned within drum I. in heat transmitting relation thereto. It will be understood that heater 54 is stationary and that drum it rotates around said heater. For this purpose, heater 54 may be carried by a part 86 mounted on a suitable support (not shown). If desired, a similar heater may be mounted in drum H as indicated by the heating support part v 8', and also, if desired, either or both of the drums 24 and 28 may be provided with a stationary electric heater such as the electric heater 54. It will be understood that a heater may be placed in any one or more of the drums I4, I6, 24 and 26.

subjected to the heat and pressure applied thereto by the roller engaged part of the lower run of band In in the heat and pressure applying zone extending longitudinally of housing 30. As

a result of pre-heating the heat-scalable material, the latter is softened and thereby conditioned for securernent under the action of the bands in the heat and pressure applying zone.

This improves the sealing action of the bands and renders the latter effective on the heat-sealable material as soon as the latter enters the heat and pressure applying zone and makes it possible to speed up the travelof bands In and I2. The degree of pre-heating of the heat-sealable material can be regulated by the temperature of the preheating means and/or by the speed of travel of bands In and I2, and also by the length of the adjacent band portions NA and HA in the preheating zone, which may be varied by using bands I? of different lengths as may be required. To enable the use of bands I2 of different lengths the shaft of drum 26 may be mounted in an adjustable bearing for increasing or decreasing the distance between the shafts of drums 26 and 24. i will be understood that the interior of tubular material It) is provided with a strip of paper or other suitable means for preventing the inner surfaces of the opposite sides of said tubular material from adhering to each other, said paper being removed after the marginal portions TI and T of the tubular material are heat-sealed to each other.

While we have shown and described the pre- 4 ferred embodiment oi! our invention, it will be understood that the latter may be embodied otherwise than as herein specifically illustrated or describedand that in the apparatus herein disclosed, certain changes in the details of construction and in the arrangement of parts may be made without departing from the underlying idea or principles of the inirention within the scope of the appended claim.

Having thus described our invention, what we claim and desireto secure by Letters Patent is:

In heat-sealing) apparatus. upper and lower endless movable bands having adjacent and confronting longitudinally extending companion runs between which the heat sealable material is engaged during the travel of said bands, a housing positioned in the space between the upper and lower runs of the upper band, a bracket mounted for pivotal movement and pivotally connected to said housing, a plurality of rollers carried by said housing and engaging the lower run of said upper band, a heater in said housing for heating saidrollers whereby to heat said rollers for heating a said lower run of said upper band, and spring means connected to said housing for pressing the rollers against said lower run of the upper band.

ARTHUR A. GARDNER. JOHN G. MACCORMACK.

I REFERENCES orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 

